In their most basic form, hair care compositions contain a film-forming resin, typically a polymer. The resin can be applied to the hair in the form of a spray, a gel, a mousse, a rinse, a lotion, a conditioner or a shampoo.
In aerosol hair spray systems, the resin usually is dissolved in an organic solvent, such as ethanol or isopropyl alcohol, and delivered via a propellant, which is usually a volatile hydrocarbon. These systems are becoming less desirable due to the consumers perception that alcohol in hair sprays can dry and damage hair, and due to environmental regulations limiting the emission of volatile organic compounds (VOC) into the atmosphere. As used herein, a volatile organic compound is an organic compound containing from 1 to 10 carbon atoms, and which has a vapor pressure of at least 0.1 mm Hg at 20.degree. C. There is an on-going effort by the hair care industry to replace VOC with water. However, the inclusion of significant amounts of water in hair fixative compositions has created problems relating to solubility and dispersability of the hair fixative resin in the compositions, to application of the hair fixatives to the hair and to performance of the hair fixative once applied to the hair.
There is a need in the industry for low VOC, aqueous-based, hair fixative compositions and hair fixative polymers which are dispersable or soluble in water, which can be applied readily to the hair, and which provide acceptable hair fixative properties, such as strength, i.e., holding power or stiffness, humidity resistance, film clarity, aesthetics and removability from hair using conventional shampoo and/or water.
One such approach to lower VOC hair fixatives is disclosed in U.S. Pat. No. 5,021,238, in the name of Martino et al. Two-phase, aqueous-based, hair-fixing aerosol systems which utilize dimethyl ether as a propellant are disclosed. The system can be shaken to form a semi-stable emulsion or mixture which is stable for a time sufficient for spraying.
Another approach to significantly reducing or totally eliminating VOC in hair fixatives is the use of water-dispersable or water-soluble polymers in an aqueous-based hair fixative gel. Such gels which are available currently utilize poly(vinyl pyrrolidone) (PVP) or derivatives thereof, such as poly(vinyl pyrrolidone/vinyl acetate) copolymers (PVP/VA), as the hair fixative resin contained therein. PVP is very sensitive to water or humidity, which deteriorates the fixative properties. It is desirable, then, to find a water-soluble polymer to replace PVP. The polymer should be less sensitive to water, form clear films upon drying, and provide the hair fixative gels with hair fixative properties which are as good as or better than hair fixative gels which contain PVP as the fixative resin.
Hair conditioning agents are functional additives used in hair care products such as lotions, shampoos, creme rinses, mousses and setting gels to improve the tactile and physical properties of hair. Cationic quaternary ammonium compounds, both mono-and di-functional, low molecular weight quaternary ammonium salts and certain high molecular weight polymers, are employed as conditioning additives in hair care products such as shampoos, conditioners, creme rinses, mousses, sprays and setting gels to impart wet and dry combability, improve feel, enhance curl retention and impart antistatic properties to hair. The Cosmetics, Toiletries and Fragrances Association (INCl) has established a designation index for compounds employed in cosmetic and toiletry products. Two low molecular weight quaternary ammonium compounds that are commonly used in hair care products because of their low cost are stearylbenzyldimethylammonium chloride (INCl designation--stearalkonium chloride) and cetyltrimethylammonium chloride (INCl designation--cetrimonium chloride).
The high molecular weight, cationic quaternary ammonium polymers (polyquats) are being used increasingly in hair care products because of their reported advantages over the simple quaternary ammonium salts in enhancing wet combability, mending split ends and improving appearance. Commonly used polyquats include: UCARE.TM. Polymer JR (INCl designation--Polyquaternium 10) from Union Carbide, a quaternized cellulose; Gafquat.TM. (INCl designation--Polyquaternium 11)from International Specialty Products, a quaternized copolymer of vinylpyrrolidone and dimethylaminoethyl methacrylate; and Merquat.TM. 550 (Polyquaternium 7) from Calgon, a homopolymer of dimethyldiallylammonium chloride.
These quaternary ammonium conditioning additives have in common the quaternary ammonium functional group: ##STR1## where R.sub.1 through R.sub.4 may be various substituted or unsubstituted alkyl or aryl substituents, or in the case of the polyquats, represent alkylene or arylene segments of a polymer chain. Associated with the positively charged quaternary ammonium nitrogen atom is a negatively charged counterion. This anion, X.sup.31 may be a halide, hydroxide, methylsulfate or similar negatively charged group.
While it is known that copolymers of vinylpyrrolidone and quaternary ammonium compounds are used as hair conditioning additives in hair conditioning compositions, it is desirable to develop new polymers which can be used as a hair conditioning additive.